Rainwater collecting on impermeable surfaces such as structures and pavement can create opportunities for water onsite reuse and problems for onsite or offsite storm water management systems. For both reuse and rainwater management, rainwater collecting on impermeable surfaces may be channeled into a rainwater detention/retention tank. The rainwater detention/retention tank may be used to store and slowly release collected rainwater to the sewer or stormwater management system (detention) or to manage collected rainwater onsite through soil infiltration, dispersion, and or recycling/reuse (retention). The term “storage tank” will be used herein to refer to a tank used for either rainwater detention or rainwater retention.
A storage tank is typically part of a larger rainwater collection system comprising ancillary components such as pipes, valves, pumps, and the like. The storage tank itself and the ancillary components forming the rainwater collection system may be made of any suitable material such as plastic, fiberglass, concrete, or steel.
At least some of a rainwater collection system, and often the entire rainwater collection system, is typically exposed to the elements. The storage tank and ancillary components forming the rainwater collection system can thus be exposed to temperatures below the freezing point of water and thus are susceptible to damage when freezing water within the rainwater collection system expands.
The need thus exists for systems and methods for reducing the risk that rainwater collection systems will be damaged by freezing water.